The first year of this study was designed to organize a collaborative effort among six laboratories aimed at repeating the major published works dealing with transmission of inflammatory bowel disease to animal models and the cultivation for viral agents in patients with inflammatory bowel diseases. After establishing channels for exchange of reagents and materials, mechanisms for regular communication among investigators and protocols with predetermined methodology, the investigators were to attempt to transmit inflammatory diseases to rabbits, using the methods described in the literature, after consultation with the authors. The investigators also agreed to attempt to transmit granulomas to the foot pads of mice using filtrates prepared from human tissues, utilizing methodology described in previous reports. Finally the investigators agreed to prepare tissue filtrates obtained from patients with inflammatory bowel diseases and from control tissues obtained from patients with other bowel diseases and to attempt to cultivate viral agents from these tissues using the two differing methodologies described by Aronson, Phillips and Beeken and by Gitnick, Shibata and Arthur. Attempts at reproducing the transmission of inflammatory bowel diseases to intraserosally inoculated rabbits have been undertaken. These studies are currently under way. Viruses have been successfully cultivated reproducing the data by Gitnick, et al and attempts are now under way to reproduce the data reported by Aronson, Phillips and Beeken. Similarly, transmission of granulomas to mouse foot pads is under investigation, but these studies are in their early stages and results are not yet available. More importantly, active collaboration among six laboratories has been undertaken. A free exchange of information and data of ongoing work has resulted in a vigorous collaborative effort. Investigators who published data to be confirmed are actively working with other investigators whose job it is to confirm or negate the results, thus insuring that criticism regarding the adequacy of attempts at confirmation should not result.